Improvement in platform-scales



STRONG ea ROSS.

Platform Scales.

Patented May 24, 1859.

UNITED STATES PATENT OFFICE.

FRANCIS M. STRONG AND THOMAS ROSS, OF BRANDON, VERMONT.

I-MPROVEM ENT IN PLATFORM-SCALES.

Specification forming part of Letters Patent No. 24,162, dated May 24,1859.

To all whom it may concern:

Be itknownthatwe, FRANCISM. STRONG and THOMAS Ross, both of Brandon, inthe county of Rutland and State of Vermont, have invented eertain newand useful Improvements in Weighing-Scales; and we do hereby declarethat the following is a full, clear, and exact I description thereof,reference being had to the accompanying drawings, making part of thisspecification, in which- Figure 1 is a plan showing the arrangement oflevers; Fig. 2, a front elevation of the same; Fig. 3, a sectionalelevation showing the manner of constructing the shafts A and the mannerof combining the platform with the levers; Fig. 4, a section showing the-manner of sustaining the shaft 0; Figs. 5

and 6, plan and elevation of portions of shaft '0, showing the manner ofcombining the several parts composing the said shaft; Figs. 7 and 8, twoviews of the improved connecting-loop Fig. 9, a sectional view showingthe manner of constructing and adjusting the nose-iron at the end of thearm H of the transmitting-lever, and Fig. 10 a section of the bearing Dand bed-plate on which the bcarin g V rests.

Our invention relatesto platform-scales for railroad and other purposesrequiring great length of platform. The arrangement of levers weconsider as an improvement upon double weighing-machines heretoforeused; and it consists of a series of parallel shafts A A A and arms B BB, Figs. 1 and 2, all the arms being connected with'and acting upon thecompound shaft 0, which transmits the force through its arm II to thescale or weigh-- jug-beam in the usual manner. The main levers A B A Bhave equal power and are all alike, except that the two composing thecen of the piers. A portion of one of the standards is shown at M, Fig.4.

The manner of coupling the shaft 0 is shown at Figs.,5 and 6. The endsof the several sections composing ithave flanges Pcast on them. Theseflanges have ears h h projecting from them." The ears h on the frontside of 'one-section of the shaft rests upon the ear h on the front sideof the other section to which the first is to be coupled. The other earsh h are similarly situated, but are connected together by a link Z, theforce applied to the shaft tending to separate these, while the firstare forced together. The surfaces of the ears h h, which come incontact, are made convex and concave to keep them in position. Thismanner of connection allows the shaft 0 to act freely upon itsknife-edges, even if thrown consid-. erably out of line, and that too,without materially affecting the accuracy of the weiglr ing action, asthe knife-edges, both the one which sustains the shaft and the one towhich the arm B is connected, areinserted in the same part of the shaftand cannot be changed in theirrelative positions by any change which maytake place in the supports or foundations.

In Figs. 4:, 5, and (i, I represents the loops connecting the leversABto the shaft 0, these levers being connected at what we term the frontside of shaft 0.

The manner of suspending the shaft is shown in Fig. 4. v M is a portionof the standard, through which an opening is cast to admit the flangedplug a, the flange projecting beyond the opening and resting upon thestandard. Through this plug a pin 1) passes, and from this the links (Z(Z depend. These links take in the block 0, upon which the knife-edge ofshaft 0 rests. This manner of hanging the lever permits the block toadjust itself to the knife edge, and also allows the shaft to oscillatelaterally and longitudinally, obviating any tendency to cramp, and doesthis without any rocking motion of the block. In this way thefineness'of the knife-edges is preserved to secure that delicacy soessential to the sensitiveness and accuracy of the machine. This is mainlyelfected by suspending the block from two separate points'and twolinks. 7

The loops used to connect-the lovers are shown at Figs.7 and S, andhavet-heir eyes, (which are the bearing parts in which the knife-edgesrest,) instead of being formed of one solid piece-with the bow, madeseparate and joined to the'bow by a joint similar to a rule-joint,.theaxis of this joint being at right angles to the-axis of the eyes. Thisinsures av perfect bearing the whole length of the knife-edge, which canonly be the case in a solid loop when the eyes are truly cylindrical andthe knife-edge lies parallel to the axis. This construction of looprenders great accuracy in fitting unnecessary, and secures at all timesa perfect bearing.

The nose-iron L, Fig. 9, is fitted to and slides in a slot in the end ofthe transmitting-arm H, Fig. 1. It has a projecting flange at bottom tosustain the strain which would otherhole is drilled somewhat deeper thanthe screw is intended to enter,for the purpose of receiving anindia-rubber' or other spring f, which presses against the screw andholds it firmly against the cross-bar at the end of the arm to which theother end of the screw is fitted, a pin being inserted through the screwwithin the bar. In this way the nose-iron L, which is the nut of thescrew, is held firmly, in position, may be readily adj usted, and'greatcare in fitting the parts is rendered unnecessary.

The bearing D,Figs. 3 and 10, has its under surface convex in thedirection of its length, and has also a round tenon projecting downwardfrom it and entering-ahole in the bedplate onwhich it rests, the convexsurface being for the purpose of allowing the bearingpiece to rockslightly,so that the pressure may be equally distributed over its wholelength, while at the 'same time the tenon permits it freely to assumethat position which will insure the proper bearing of the knife-edgeswithout binding.

The manner of combining the platform with the several bearings is shownat Fig. 3, in which A represents one of the several bearings, the'shaftof the main lever with its center knife-edge resting upon the bearing D.E is an intermediate bearing-piece resting upon the platforni supportingknife-edge of the leverA. The upper surface of this bearing-piece hastwo cups or concaves cast in-it,

in which are inserted spheres. The shoe N is attached to the under sideof the platform and. has corresponding concaves on its under surface,and these rest upon the spheres, the

object being to relieve the knife-edges from' any lateral shock whichthe platform may receive, as this shoe upon which the platform timbers(not shown) rest can move freely upon the spheres or balls, while thebearing-picce E remains unmoved upon the knife-edge.

The operation will be readily understood. Weight being placed upon theplatform acting through the shoes, balls, and bearingpieces E upon theknife-edges tends to turn the shafts A and consequently depress the endof the arms B. These being connected to the shaft 0 tend in like mannerto turn it and depress the end of the transmitting-arm I-Lwhich actuatesthe weighing-beam where the weight is indicated in the usual manner.

Ve have thus described the mode' of application of our said invention,which we have successfully reduced to practice; but we do not wish to beu derstood as limiting our claim-of inventiolz to such special mode ofapplication, as other modes of 1 application may be adopted.

That We claim as our invention, and desire to secure by Letters Patent,is

1. Arranging theseries of rocking levers which sustain the platform withtheir shafts all parallel and with the arms of all of them in the sameline, except those constituting the inner section, which are inclined,substantially as described, in combination with thetransmitt-ing-leverabove whiel, connects with the scale-beam, to theshort arms of which they are all suspended at equal distances from theaxis of vibration, substantially as and for the purpose described.

2. The method of connecting the several sections of the shaft of thetransmitting-levcr by means of projections and links, substantially asdescribed, for the purpose of, enabling it to yield freely toinequalities or variations in the supports, that it may vibrate freelyand without binding, and thereby trans- .mit the weight accurately tothe scale-beam,

self-adjusting, that the knife-edges may bear without binding, as set.forth.

5. In combination with the nose-iron adjustable by a screw in the end ofthe transmitting-lever, the employment of a spring bearing against theend of the adjustingscrews, substantially as described, and for thepurpose set forth.

FRANCIS M. STRON G. THOMAS ROSS.- Witnesscs:

- JOHN F. ESTABROOK,

ROBT. FORBES.

